The main difference between the BDP-103EU and BDP-103D is the BDP-103D's incorporation of the Darbee Visual Presence processor.  The BDP-103EU is a reference quality Blu-ray Disc player and has won numerous awards. The BDP-103D is based on the BDP-103EU and shares most of the same features.

The Darbee processor is a video enhancer that provides greater clarity and increases the perception of depth by embedding stereoscopic depth cues within the video, resulting in a more dynamic, lifelike experience. The Darbee's processing level is adjustable, which allows you to customise it to your particular taste. Unlike many other image enhancers or sharpeners, the Darbee processor does not alter the image in a global fashion, so it is able to reduce the amount of image artifacts that are created, and it does not adversely affect calibrated settings such as contrast, gamma, and colour.  The original BDP-103EU is known for its accuracy in reproducing video from all kinds of discs. The BDP-103D takes one step beyond reference quality accuracy. 

When the Darbee Visual Presence enhancement is turned off, it is a reference quality player just like the BDP-103EU. When the Darbee Visual Presence enhancement is turned on, the user has the option to fine tune the video to his/her own liking. In summary, if you are looking for a quality player that accurately reproduces video, the BDP-103EU is the right choice; if you are looking for a more customised experience beyond standard picture adjustments, the BDP-103D provides additional possibilities to fine tune your viewing experience.